This invention relates to a backlight device, a liquid crystal display device arranged to be applied with light to a rear surface of a transmissive liquid crystal display panel by the backlight device, and an electronic apparatus using the liquid crystal display device.
For example, a device shown in FIG. 13 is known as a backlight device used in an electronic apparatus such as a mobile phone including a liquid crystal display device. This backlight device 101 includes a drive substrate 103 directly attached with a plurality of light sources 102 such as a white LED (light-emitting diode), a white reflection sheet 104, a light guiding plate 105, a diffusion sheet 106, two prism sheets 107 and 108, and a frame 109.
Within the frame 109, there are received the two prism sheets 107 and 108, the diffusion sheet 106, the light guiding plate 105, and the reflection sheet 104 in this order. Finally, the drive substrate 103 is received within the frame 109, and the frame 109 and the drive substrate 103 are joined by a clip 110, to form the backlight device 101.
Light emitting surfaces 102a of the light sources 102 and a light incident surface 105a of the light guiding plate 105 are disposed to confront each other. The light emitted from the light emitting surfaces 102a of the light sources 102 are guided from the light incident surface 105a into the light guiding plate 105. The light guided into the light guiding plate 105 is refracted by the diffusion sheet 106 and the two prism sheets 107 and 108, and illuminates a rear surface of the liquid crystal display panel 111. (cf. for example, patent document 1)
[patent document 1] Published Japanese Patent Application Publication No. 2002-75038 (paragraph [0013] and so on)